Deep fat fryer with improved heat transfer

Abstract

An improved heat exchange mechanism for a deep fat fryer is described. The improvement includes a baffle plate wherein the walls are corrugated and horizontally aligned holes are provided along the length of the plate with the interior two rows of such holes having decreasing diameter in the direction of flow of the combustion gases through the heat tube. In addition, holes are formed at the edges of the corrugations. A burner shield is provided restricting the flow of secondary air to the burner tube.

1. A deep fat fryer, comprising:
 a housing; 
 a vat within the housing for containing cooking oil; 
 at least one heat tube extending through the vat; 
 a burner assembly adjacent each heat tube, the burner assembly sending a flow of hot gases through the heat tube to heat walls of the heat tube; and 
 at least one elongated baffle plate disposed in the at least one heat tube, said plate being corrugated with a plurality of angled walls, each wall being rectangular and disposed at an angle to the flow of hot gases, a face of each wall containing a plurality of circular holes with said holes in said wall being aligned in horizontal rows wherein diameters of the holes in at least one of said rows decrease along a length of the plate in a direction of said flow. 
 
   
   
     2. The fryer of  claim 1  wherein the face of each wall forms four vertically aligned holes. 
   
   
     3. The fryer of  claim 2  wherein two horizontal rows of said holes of decreasing diameter are formed. 
   
   
     4. The fryer of  claim 3  wherein said two rows are the interior rows of holes. 
   
   
     5. The fryer of  claim 1  wherein adjacent walls define an interior angle of about 60°. 
   
   
     6. The fryer of  claim 5  wherein a portion of at least one hole is formed at a junction of adjacent walls. 
   
   
     7. The fryer of  claim 6  wherein the junction of each adjacent wall forms an edge and each edge forms a portion of at least one hole. 
   
   
     8. The fryer of  claim 1 , wherein each wall has a first edge that forms a portion of two holes and a second edge that forms a portion of one hole. 
   
   
     9. The fryer of  claim 1  further comprising a shield surrounding the burner access to each heat tube to restrict secondary air to said burner. 
   
   
     10. The fryer of  claim 9  wherein each shield is a frame surrounding the burner and coupled to the heat tube and forming a notch of predetermined dimensions therein as the sole opening for pilot ignition flame to said burner. 
   
   
     11. A deep fat fryer, comprising:
 a housing; 
 a vat within the housing for containing cooking oil; 
 at least one heat tube extending through the vat for heating the oil; 
 a gas burner mounted at an entrance of each tube; and 
 a burner shield coupled to said burner, the burner shield surrounding an entrance to said tube and restricting an entrance of secondary air to said burner, 
 further comprising an elongated baffle plate disposed in the at least one heat tube, the plate being corrugated with a plurality of walls, each wall at an angle to the other walls, each wall being rectangular and disposed at an angle to a flow of hot gases through the heat tube, a face of each wall forming a plurality of circular holes with said holes in said wall being aligned in horizontal rows, and a diameter of the holes in at least one of said rows decreasing along the length of the plate in the direction of said flow. 
 
   
   
     12. The fryer according to  claim 11  wherein the face of each wall forms four vertically aligned holes. 
   
   
     13. The fryer according to  claim 11  wherein adjacent walls define an interior angle of about 60°. 
   
   
     14. The fryer according to  claim 11  wherein a portion of at least one hole is formed at a junction of adjacent walls. 
   
   
     15. The fryer according to  claim 11  further comprising a housing surrounding said burner and extending into a first end of said tube. 
   
   
     16. The fryer according to  claim 11  wherein the burner shield has a substantially rectangular outer surface.